1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to the structure of barrier ribs formed on a rear substrate and a plasma display panel in which barrier ribs are formed.
2. Discussion of Related Art
In general, a plasma display panel apparatus includes discharge cells formed between a rear substrate having barrier ribs formed therein and a front substrate opposite to the rear substrate. The plasma display panel apparatus implements images by light-emitting phosphors with vacuum ultraviolet rays generated when an inert gas within each of the discharge cells is discharged by a high frequency voltage.
FIG. 1 is a plan view of electrodes formed in a general plasma display panel. FIG. 2 is a cross-sectional view of a discharge cell of the general plasma display panel.
The discharge cell is formed on a rear substrate 18 opposite to a front substrate 10 by a plurality of barrier ribs 24 partitioning discharge spaces.
An address electrode 12X is formed on the rear substrate 18. Scan electrodes 12Y and sustain electrodes 12Z are formed in pairs on the front substrate 10. As shown in FIG. 1, the address electrode 12X cross the scan electrodes 12Y and the sustain electrodes 12Z. The rear substrate 18 shown in FIG. 2 is rotated by 90°.
A dielectric layer 22 for accumulating wall charges is formed on the rear substrate 18 having the address electrode 12X formed therein.
The barrier ribs 24 are formed on the dielectric layer 22, forming the discharge spaces between the barrier ribs. The barrier ribs 24 prevent ultraviolet rays generated by a discharge and a visible ray from leaking to neighboring discharge cells. Phosphors 26 are coated on surfaces of the dielectric layer 22 and the barrier ribs 24.
An inert gas is injected into the discharge space. The phosphors 26 are excited by ultraviolet rays generating during a discharge of the gas, generating one of red, green and blue visible rays.
Each of the scan electrodes 12Y and the sustain electrodes 12Z formed in the front substrate 10 includes a transparent electrode 12a and a bus electrode 12b. The scan electrodes 12Y and the sustain electrodes 12Z cross the address electrode 12X. A dielectric layer 14 and a protection film 16 covering the scan electrodes and the sustain electrodes are also formed on the front substrate 10.
The discharge cell constructed above is selected by a counter discharge between the address electrode 12X and the scan electrodes 12Y, and then has its discharge sustained by a surface discharge between the scan electrodes and the sustain electrodes 12Y, 12Z, thus radiating a visible ray.
FIG. 3 shows the structure of barrier ribs formed in a rear substrate of the general plasma display panel.
A region on the rear substrate 18 may be classified into a display region on which images are displayed, and a non-display region on which images are not displayed. A plurality of barrier ribs 24 is formed in the display region in lattice form. A Side Barrier Rib (hereinafter referred to as “SBR”) 30 is formed on the non-display region.
The SBR 30 is disposed within the non-display region. The SBR 30 functions to prevent sealing paste or material for adhering the front substrate 10 and the rear substrate 18 from entering the display region and also to prevent the barrier ribs 24 within the display region from being damaged by pressure applied for adhesion.
At this time, the barrier ribs 24 formed on the display region has a step in which the height of central barrier ribs is lower than the height of outer barrier ribs in a manufacturing process. The SBR 30 also has a step with the central barrier ribs. Therefore, problems arise because the adhesion density of the substrate is decreased and noise is generated in the panel.
Furthermore, the central barrier ribs of the display region do not isolate the respective discharge spaces due to the steps of the barrier ribs 24 and the SBR 30. This results in crosstalk fail.